The invention is directed to a simple and inexpensive means to automatically change the effective position of the string or bridle attachment on a kite. The word kite as used in this disclosure refers to any airfoil which is lifted by the wind and tethered by a string.
One of the inherent problems with kites is that for the kite to perform well the string or bridle must be attached at a particular point relative to the center of the airfoil surface. The ideal point of attachment varies depending on the wind velocity. Attempts to change the position of the string attachment and thereby alter the attitude of the craft for different wind velocities have been made in the past. The most usual of these adjustments is the provision of a plurality of notches on the string attachment member. However this adjustment must be made manually, requires knowledge of the wind velocity, and is not easily changed to compensate for shifting winds without retrieving the kite.
One prior art patent which controls the attitude of a kite by moving its bridle point is U.S. Pat. No. 4,280,675. This kite is controlled in two discrete steps in response to both release of tension on the cord and the wind. It requires a mechanism using springs and cams and is not completely automatic.
The acrobatic kites can change their attitude in response to motions of the kite handler. The success of these motions depends on the skill of the kite handler.
There still exists a need for a kite attitude adjustment which is dependent on wind strength and is continuous, automatic, and reversible.